Filling-Mining Technology Helps Build Green Coal Mining 20 Aug 2018
Shanghe Coal Mine is located in Yulin City, Shaanxi Province, about 15 kilometers northeast of Yulin City. In 2008, the approved production capacity of the mine was 300,000 tons/year. In March 2013, the final approved production capacity of the mine was 600,000 tons/year. The mining area is located on the southern edge of the Mu Us Desert. The area of the mine field is 2.977 square kilometers. The existing geological reserves are 11.417 million tons, the recoverable reserves are 4.797 million tons, and the remaining service life is about 8 years.
Coal mining and environmental protection, urban development, water resources protection and other issues have been entangled in contradictions, plaguing the development of enterprises. How to maintain the economy while maintaining the green hills and clear waters? The Shanghe Coal Mine in Yulin City is the first to implement the filling-mining technology, that is, to transport sand, fly ash, paste and other filling materials to the coal mine goaf, and to carry out coal mining under the protection of the filling body. The filling-mining is a green mining technology. The important part of the system is the most effective way to improve the recovery rate and reduce environmental damage. It not only realized the mining of coal under the building, under the water, and under the railway, but also greatly extended the service life of the mine, and improved the resource recovery rate, solved the problem of solid waste discharge, and eliminated the efflux of pollutants and achieved green mining.
Exploration: Implementing filling-mining technology
In response to the call for promoting coal mine application to promote filling-mining, increase the recovery rate of coal resources, extend the service life of mines, effectively protect the water source from damage, prevent surface subsidence, and eliminate the legacy of large areas of the goaf after coal mining. Many safety hazards, Shanghe Coal Mine of Yulin City, on the basis of many field trips organized by the Coal Bureau of Xiangyang District to Inner Mongolia, Hebei, Shandong and other places, decided to introduce colloid filling-mining technology in July 2016 to carry out charging and mining experiments and construct green coal mining enterprise.
In March 2017, Shanghe Coal Mine was approved by the Yuyang District Government of Yulin City and designated as a pilot mining coal mine by the Coal Bureau of Yuyang District. In June 2017, Shanghe Coal Mine entrusted Xi'an University of Science and Technology, Shaanxi West Mine Engineering Survey and Design Co., Ltd. and Shaanxi Shicheng Mining Co., Ltd. to compile the “design of aeolian sand-like paste filling-mining scheme for Shanghe Coal Mine in Yulin City”. Shanghe Coal Mine started the application of filling-mining technology. After several months of construction and commissioning period, a series of tests were carried out on the 3216 working surface for the proportioning of raw materials, mechanical equipment and process, at the end of August, five strips were successfully filled. In September 2018, Shanghe Coal Mine invited relevant experts to review the design of the filling-mining plan based on the actual inspection of the underground filling test site. In January 2018, Shanghe Coal Mine commissioned the design unit to make appropriate adjustments to the strip mining parameters, mining backfilling process, monitoring plan, and transportation, ventilation, drainage and other systems based on the conditions of underground mining and the specific problems encountered during the test mining process.
Shanghe Coal Mine is strictly implemented according to the design plan. The ground construction filling station includes aeolian sand storage yard, aeolian sand raw material warehouse, cement silo, fly ash silo, water storage tank, factory building, etc.; EBZ200 cantilever type roadheader is used for test work surface Coal cutting, ZL18FB tire type explosion-proof loader for coal loading, using WC3 type explosion-proof rubber wheel car to transport coal. At present, the 3216 test face has completed the first stage of 14 strips and goaf filling, the second stage of six odd-numbered strip coal pillars and its goaf filling, and the third stage of the odd-numbered coal pillar replacement work is underway, and the acceptance progress of the design requirements is basically met. After monitoring, the measured strength of the filling body is 8.22MPA, which is greater than the design requirement of 6.47MPA, which meets the requirements. The application of this technology in Shanghe Coal Mine has achieved partial results in the coal mine 3216 working face. Through continuous summarization, the following conclusions are made: First, the ground equipment and facilities work stably and normally, and the filling amount is guaranteed; second, the underground construction, the process is reasonable and effective, does not produce the work and all kinds of waste; the third is in the filling Under the premise that the body is stable and the bearing pressure meets the displacement strength, the topping condition is good, and the conditions for the post-charge replacement mining are satisfied; the fourth is that for the cost situation, the current comprehensive cost is within the acceptable range, and the project is continuously carried out, and the reduction is also carried out. The cost space; Fifth, through the data from the monitoring equipment and facilities of the well, the surface has not been significantly subsided, and the water resources and ground facilities in the mine are protected from damage; The introduction and the gradual improvement of the project not only increased the income for the mine, but also solved the problems such as the collapse of the goaf, surface damage and sewage discharge faced by Shanghe Coal Mine once and for all.
In June 2018, the coal bureau of Xiangyang District led the organization of project construction, design, construction and other units and expert groups to set up an acceptance committee to conduct on-site inspection and acceptance of the Shanghe coal mine filling-mining project. The acceptance conclusion was: agree with Yuhe Coal Mine in Yulin City The staged results of the aeolian sand-like paste filling-mining project passed the acceptance test. The acceptance expert group unanimously agreed that the implementation of filling-mining technology in Shanghe Coal Mine is the first case in the province, and it has actively explored the filling-mining of coal mines in Shaanxi, which has a strong practical significance.
Results: Source to solve the problem of surface settlement
Promote the transformation of the coal industry to “ecological and environmental protection”. The first level is to minimize the impact on the ecological environment; the second level does not affect the ecological environment; the third level, actively improve the ecological environment. Shanghe Group took the lead in implementing filling-mining, realizing the transition from passive governance to active prevention and control that Yulin coal industry expects. It is a vivid example of the transformation of coal industry into “ecological environment-friendly”. The implementation of filling-mining in Shanghe Coal Mine can extend the service life of mines for about 5 years and play a good role in the local economy, employment, taxation and the stability of the people's lives. In short, the application of filling-mining technology, under the premise of safer, improves the recovery rate, and effectively protects the water source from damage, the surface does not collapse, and eliminates many hidden dangers left by the goaf after coal mining. It has also relatively increased the economic value of coal mines and brought certain social benefits to the localities.
How to copy "Shanghe Practice"
With the active guidance and strong support of the coal authorities, the Shanghe Group has invested a lot of manpower, financial resources, material resources and time to overcome various difficulties and made painstaking efforts to explore a new path of green mining. It is not easy to form a "Shanghe Practice". For a coal-producing city like Yulin, how should the “Shanghe Practice” be replicated under the current circumstances? The government should strengthen the support for technical transformation projects. The use of central budgetary funds such as coal mine safety reform and coal industry upgrading to support the implementation of filling-mining in coal mines shall provide supporting policies for the provincial finance, and at the same time implement the preferential taxation of coal resources for filling-mining, and reduce the cost burden of filling-mining enterprises. Relevant departments of local governments should actively support coal mining enterprises to carry out filling-mining work in order to speed up the promotion of filling-mining technology. In addition, from the national macro level, it should be considered to include coal mine by-products such as sandstone, vermiculite, paste and other tailings waste slag as the main filling materials and coal products for filling-mining in the comprehensive utilization of resources, and enjoy the comprehensive utilization of national resources. Preferential policies.
Shanghe Group took the lead in implementing filling-mining technology and explored a new path for green mining and sustainable development of coal mining enterprises in Shaanxi. “Shanghe Practice” is worthy of reference and promotion by other coal mining enterprises. At present, the filling-mining technology implemented by Shanghe Group has been promoted to ten water conservation coal mines in Xiangyang District.